Recently, there is a growing demand on high-resolution, high-quality images in various application fields. With the increase in the resolution and quality of the image, an amount of information for the image is also increased.
The increase in the information amount results in the introduction of a device having various capabilities and a network having various environments. With the introduction of the device of the various capabilities and the network having the various environments, the same content can be used with a variety of quality.
More specifically, as a user equipment can support an image of a variety of quality and an implemented network environment is diversified, an image of normal quality is used in a certain environment, whereas an image of higher quality can be used in another environment.
For example, a consumer who purchases a video content in a portable terminal can watch the same video content with a larger screen and a higher resolution by using a large-screen display at home.
A broadcasting service with a high definition (HD) resolution has recently been provided, and thus many users are accustomed to high-definition, high-quality images. Further, in addition to HDTV, service providers and users are paying attention to ultra high definition (UHD) having a resolution four times higher than the HDTV.
Therefore, in order to provide an image service requested by a user in various environments according to quality in various manners, it is necessary to provide a scalability to image quality (e.g., image picture quality, image resolution, image size, video frame rate, etc.) on the basis of a high-efficient encoding/decoding method performed on large-capacity video. In addition, there is a need to discuss various image processing methods accompanied by such a scalability.